Lactose

lactose_structure.png
By: Alayna

Properties

Molar Mass: 342.29648 g/mol
Formula: C
12H22O11
Density: 1.53 g/cm
3
Melting Point: 202°C (396°F)
Boiling Point: Decomposes
Solubility: Soluble in water
Physical State: White Crystals/White powder
Bond type: Covalent


Percent Composition

Percent Composition by mass:

  • Carbon- 42%
  • Hydrogen- 6.5%
  • Oxygen- 51.4%

Percent composition by number:
  • Carbon- 26.7%
  • Hydrogen- 48.9%
  • Oxygen- 24.4%

Uses and Importance

lactose_poder.jpg
What is Lactose?
Lactose is a type of sugar that is naturally present in milk and milk products. Lactose is in many food products and medications. Lactose in used as a substrate lactic acid bacteria in dairy products (yogurts, cheeses). Its is the bacteria that turns the milk sour. These certain bacterica breaks down lactose into lactic acid that solidifies the milk. Lactose is the most important carbohydrate of milk. Lactose is also important in the medical industry for certain medicines and prescriptions. Lactose is also used as a tablet filler. Lactose is not expensive and it is non-toxic. People who are lactose intolerant do need lactose in their bodies to be healthy. Lack of calcium can cause damage later on in life. Therefore, lactose is very important to the world.


What other products is lactose in?
Milk and other milk products are added to processed foods:


  • Bread
  • Waffles
  • Pancakes
  • Bisquits
  • Cookies
  • Processed breakfast foods
  • Instant potatoes, soups, and breakfast drinks
  • Chips
  • Processed meats (bacon, sausage, hot dogs, lunch meat)
  • Margarine
  • Salad dressings
  • Protein bars
  • Click here for more information

Lactose is also in medicines including birth control, over the counter medicines. These medicines do cause symptoms in the people who have lactose intolerance.

History

Background Information: Lactose is the sugar that makes up 2-8% of the solids in milk. Lactose occurs in two isomeric forms a-lactose and b-lactose. Lactose was discovered by Fabriccio Bartoletti in 1619. We need lactose in our bodies. People who have lactose intolerance are at a disadvantage. They need that calcium to live. Some people can eat small amounts of foods with lactose in it. They are just not able to consume large amounts. Some have to eat an alternate. An alternative for milk with lactose would be soy milk.

Where is it found: Lactose is found in mammals and humans. It is the milk inside them. It is a source of energy for the young.

How is it obtained: Lactose is made from the two sugars, galactose and glucose. When these two sugars form a reaction together, they produce lactose.


Chemical Properties


Dehydration and pyrolysis: A-lactose loses its water of crystallization at 100°C. The loss of the crystalline structure of lactose follows the loss of the crystallization which means the lactose becomes amorphous. Heating lactose to higher temperature causes it to decompose which is called pyrolysis.

Maillard Reaction:
In aqueous solution, lactose reacts with compounds containing amino-groups. Later, at an advanced stage, yellow/brown polymers are formed and that turns the mixture to a black color. Purified lactose contains traces of proteinaceous matter. Millard reactions can't be excluded from some dry lactose preparations. A-lactose cannot absorb moisture. It has a low moisture content to prevent the millard reaction from occuring.

Fermentation:
Lactose is a substrate for micro-organisms, such as, bacteria, yeasts, and moulds. Micro-organisms require moisture. Storage of lactose under dry and cool conditions will prevent microbial spoilage.



Lactose Intolerance

Lactose intolerance is the inability to digest lactose ( which is a sugar found in milk and dairy products). Lactose intolerance is caused by a deficiency of the enzyme lactase, which is produced by the cells lining the small intestine. Not all of the people who are lactose intolerant have the digestive symptoms. Some people with this can tolerate some milk products in there diets. Lactose intolerance develops at about age 2. Some kids who are lactose intolerant do not develop the symptoms until early adulthood. African Americans, Hispanics, American Indians, and Asians are more likely to be lactose intolerant.

milk-lactose.jpg


3D Molecule
external image x-gzip.png lactose 3D molecule.bio




References

"Interactive Molecules". EdInformatics.com. 11/13/09 < http://www.edinformatics.com/interactive_molecules/3D/lactose_molecule.htm >
"Lactose". Mallinckrodt Baker, Inc.. 11-13-09 <
http://www.jtbaker.com/msds/englishhtml/l1044.htm >.
"Lactose Intolerance". National Digestive Diseases Information Clearinghouse. 11/14/09 < http://digestive.niddk.nih.gov/ddiseases/pubs/lactoseintolerance/ >
Lapid, Nancy. "What is Lactose?". The New York Times Company. 11/14/09 http://celiacdisease.about.com/od/celiacdiseaseglossarygl/g/Lactose.htm
"Introduction to Lactose". FrieslandCampina Domo. 11/15/09 <http://www.lactose.com/thumbs_1.html
"Basic Properties". FrieslandCampina Domo. 11/16/09 http://www.lactose.com/basic/chemical_properties.html.
"2.1 Covalent Bonds". W. H. Freeman and Company. 11/16/09 http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=mcb&part=A259.
""1619 in Science". Wikimedia Foundation, Inc.. 11/16/09 http://en.wikipedia.org/wiki/1619_in_science.
bender, david. "lactose". High Beam Research Inc.. 11/18/09 <http://www.encyclopedia.com/doc/1O39-lactose.html>.

Image Resources ​

"Lactose Cyclic Vertical". Creative Commons Attribution/Share-Alike License. 11/17/09 http://www.blendedschools.blackboard.com/webapps/portal/frameset.jsp?tab_tab_group_id=_2_1&url=%2Fwebapps%2Fblackboard%2Fexecute%2Flauncher%3Ftype%3DCourse%26id%3D_32372_1%26url%3D.
"Milk". Creative Commons Attribution/Share-Alike License. 11/16/09 http://blendedschools.blackboard.com/webapps/portal/frameset.jsp?tab_tab_group_id=_2_1&url=%2Fwebapps%2Fblackboard%2Fexecute%2Flauncher%3Ftype%3DCourse%26id%3D_32372_1%26url%3D.
"Wholesale Products". Creative Commons Attribution/Share-Alike License. 11/16/09 http://blendedschools.blackboard.com/webapps/portal/frameset.jsp?tab_tab_group_id=_2_1&url=%2Fwebapps%2Fblackboard%2Fexecute%2Flauncher%3Ftype%3DCourse%26id%3D_32372_1%26url%3D.

3D Molecule
"Interactive Molecules". EdInformatics.com. 11/13/09 < http://www.edinformatics.com/interactive_molecules/3D/lactose_molecule.htm >.